And how do you define the results ? What if the employee gradually slows downs working like one hour less per week every month, in a year they can go from 40 hours per week into 28 hours per week with normal work expectations.
And that wouldn't necessarily be a "bad employee trying to get more from you by doing less". For example, maybe your team performance is getting worse. Let's say you have a coworker that is sick and gets normal pay for less quality work, and another coworker that just got a baby and got less time for work. The teams got less focused on work gradually in time and the employee feels "entitled" to work less on you and do something else with his/her time